My neighbor gave my 8-year-old toy dinosaurs.

I am a little shocked. She says she is a Christian, but the Bible doesn't say anything about dinosaurs. Should I let him keep them, as long as he understands that dinosaurs aren't real? Even the PBS shows that he watches talk about dinosaurs and evolution, and how the scientists found these "bones" but the Bible doesn't say that God ever created them, and the earth is only 6,000 years old, not old enough to have "bones" that they say are MILLIONS of years old! I know that Satan tries to trick us in many ways, and this is one way that he tries to fool man into believing that there isn't a God who created the universe. How can they be bones when they are made out of ROCKS? I told my son that dinosaurs are one of Satan's many ways of tricking man, and he must talk to God before he plays with them. Am I handling this right? My first 3 were all girls, and I adopted boys, and lots of mothers tell me that boys are often attracted to these dinosaurs. So I don't know what to do. Is this just harmless fantasy play for him, or should I be worried that he may go on to believe in things like evolution?